Should We Prefer Experts to Be Autonomous?

Speaker: YE Ru

Venue: 4-311, Chengjun Court, Zijingang Campus

Abstract: When laypeople consult multiple experts—whether in courtrooms, hospitals, or public policy—they often prefer that these experts reach their judgments independently. This intuitive preference for expert autonomy has traditionally been explained by the ‘variety of evidence thesis,’ which claims that agreeing testimonies coming from independent sources are more confirmatory than dependent ones. However, this thesis has been challenged, particularly in contexts involving uncertain source reliability.In this talk, I take a novel approach by shifting focus from the informativeness of agreement among expert testimonies to the informativeness of the entire experiment of consulting experts. I present two main results. First, independence does not in general make the expert-consulting experiment more informative. For some independent group of experts, there exists a correlated counterpart group such that consulting the correlated group is more informative, ceteris paribus. Second, however, when we consider the empirical reality that expert correlation is often ambiguous, and account for decision-makers’ aversion to ambiguity, consulting independent experts will be more informative than consulting correlated ones.